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This entry was originally written by Arleigh P. Helfer, Jr. and Carol L. Maki for Red Book: American State, County, and Town Sources.
Beginning in the 1840s and burgeoning near the end of the century, immigrants from northern and eastern Europe journeyed to Michigan for employment opportunities and religious freedom. Naturalization records for Michigan are organized by county, twenty-five of which have indexes. Declarations of intentions are usually arranged by surname while other documents for the citizenship process are chronological. Records for over twenty of Michigan’s counties are cataloged by the State Archives of Michigan, thirteen of which are available online. See State Archives Circular No. 10 or their website for a current list